What is CVE-2026-31738?

CVE-2026-31738 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 3.12.18 onward and patched in 5.10.253, 5.15.203, 6.1.168 and others. CVE-2026-31738 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-31738?

CVE-2026-31738 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-31738?

Yes, CVE-2026-31738 has been patched. Fixed versions include 5.10.253, 5.15.203, 6.1.168 and others. If you are running Linux kernel 3.12.18 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-31738 actively exploited?

CVE-2026-31738 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-31738

Medium

In the Linux kernel, the following vulnerability has been resolved: vxlan: validate ND option lengths in vxlan_na_create vxlan_na_create() walks ND options according to option-provided lengths. A malformed option can make the parser advance beyond the computed option span or use a too-short source LLADDR option payload. Validate option lengths against the remaining NS option area before advancing, and only read source LLADDR when the option is large enough for an Ethernet address.

Package Linux Kernel

Published 2026-05-01

Last modified 2026-05-07

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected versions

Linux kernel versions 3.12.18, 3.13.10, 3.14 and later are affected. Fixed in 5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12, 7.0 and their respective stable series.

Affected from

≥ 3.12.18 ≥ 3.13.10 ≥ 3.14

Fixed in

✓ 5.10.253 5.10.x ✓ 5.15.203 5.15.x ✓ 6.1.168 6.1.x ✓ 6.6.134 6.6.x ✓ 6.12.81 6.12.x ✓ 6.18.22 6.18.x ✓ 6.19.12 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-31738 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/2029712fb2c87e9a8c75094906f2ee29bf08c500
Patch
Kernel patch commit
https://git.kernel.org/stable/c/602596c69a70e50d9ab8c6ae0290a01f88229dd7
Patch
Kernel patch commit
https://git.kernel.org/stable/c/901c1dd3bab2955d7e664f914c374c8c3ac2b958
Patch

8 patch commits total View all on NVD

Details

CVE ID CVE-2026-31738

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-05-01

Modified 2026-05-07

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-31738?

CVE-2026-31738 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 3.12.18 onward and has been patched in 5.10.253, 5.15.203, 6.1.168 and others. CVE-2026-31738 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-31738?

CVE-2026-31738 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-31738?

Yes — CVE-2026-31738 has been patched. Fixed versions include 5.10.253, 5.15.203, 6.1.168 and others. If you are running Linux kernel 3.12.18 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-31738 actively exploited?

No — CVE-2026-31738 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.